The present invention relates generally to machinery for assembling multi-sheet mailing pieces and inserting them into envelopes and, more particularly, to an improved right-angle-turning (RAT) device adapted for use in such a mailing system.
A production mailing system typically includes a series of modules which perform different functions, such as a cutter (for slicing a continuous paper web into sheets) or a burster (for separating a paper web having transverse perforations into sheets), an accumulator for accumulating all the sheets intended for a particular recipient, and an inserter for putting the collected sheets into an envelope. Frequently, a right-angle-turning (RAT) module will be placed between the accumulator and the inserter. However, conventional right-angle-turners are insufficiently versatile in coping with oversized or otherwise irregular collections of sheets.
Accordingly, it is an object of the present invention to provide an improved right-angle-turner which can selectively divert oversized or irregular sets of sheets out of a primary or standard paper path into a secondary paper path for special handling, in order to minimize paper jams and consequent downtime. Preferably, the device also folds each set of sheets.
Briefly, this diversion is accomplished by an apparatus and corresponding method, the apparatus including: a receiving means, for receiving the sheet and redirecting it in a chute direction at substantially ninety degrees from the feed path; a chute means, for grabbing the redirected sheet and for causing the sheet to form a buckle along a line located at approximately halfway across a width of the sheet and extending along a length of the sheet; a folder nip, disposed to grab the buckle in the sheet, for providing the sheet folded in half; and a diverter, rotatably disposed to receive the sheet folded in half, for directing the sheet to either of at least two final directions, depending on its orientation.
In a further aspect of the invention, the chute means includes: a chute feed nip, disposed at the edge of the turnplate toward which the pusher tab pushes, for grabbing the sheet and driving it onward in the chute direction; and a chute, disposed so as to receive the sheet being provided in the chute direction by the chute feed nip, the chute having a chute stop disposed a distance along the chute approximately equal to a half-width of the sheet, for continuing to receive the sheet until it stops at the chute stop and then to provide a buckle in the sheet that is caused to protrude from the chute under the continuing action of the chute feed nip, until the sheet is clear of the chute feed nip.
In a still further aspect of the invention, the receiving means includes: a turnplate for receiving the sheet, the turnplate having stops protruding from a sheet-receiving surface of the turnplate, for holding the sheet edge aligned against the stops; and a chute pusher disposed so as to have a pusher tab movable across the sheet-receiving surface of the turnplate, for pushing the sheet along the sheet-receiving surface of the turnplate in a chute direction at substantially ninety degrees from the feed path.
In another aspect of the invention, the apparatus also includes a means for acquiring information about whether to divert the sheet, and the diverter is rotated into an orientation depending on the acquired information. In particular, the means for acquiring information can be a bar code reader that scans the sheet to determine to which final path to direct the sheet.
The present invention accomplishes all of the above processing not only on a single sheet by single sheet basis, but for stacks of sheets that it forms by accumulating a series of sheets being provided over the feed path. In case of processing a stack of sheets, the entire stack is folded, i.e. the sheets are folded collectively, as a stack.